Stores Tracking Shoppers Using Phone Wi-Fi Signals

If the whole NSA/PRISM controversy hasn't been enough to scare you off the Internet, here's even more to worry about offline: Wi-Fi tracking in stores.

Sure, we're used to the cameras keeping an eye on our hands, making sure we're not pocketing something tasty to sell on eBay. We get it. But what's scary is that brick-and-mortar stores are keeping track of customer movements using Wi-Fi signals from their phones. Why? To study and map browsing habits and eventually send these patrons advertisements based on those in-store interests.

The New York Times wrote about Nordstrom, a retailer that wanted to learn more about its customers using this kind of technique. However, Nordstrom's experiments are part of an overall movement by retailers in gathering as much information about customers as possible, including behavior patterns and moods. They're doing this by using the Wi-Fi tracking method and apps, learning their gender, how many minutes they spend in the candy isle, and so on.

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According to the report, national chains like Family Dollar, Cabela’s and Mothercare, a British company, are testing these technologies. Even specialty stores like Benetton and Warby Parker – all sorts of retailers, the paper claims – are relying on this tech to determine things like customized coupons and store layouts.

"Brick-and-mortar stores have been disadvantaged compared with online retailers, which get people’s digital crumbs," said Guido Jouret, the head of Cisco’s emerging technologies group. "[Why should physical stores not] be able to tell if someone who didn’t buy was put off by prices, or was just coming in from the cold?"

Indeed, consumers have grown used to cookies, profiles and other online tools that create an online ad system catering to their tastes. Online shops like Amazon know who their customers are, have records of what they've bought and what they've glanced at in its virtual isles. Why is it different in brick-and-mortar stores? Because we've moving, we're physically being watched while online we're merely leaving a digital trail.

Cisco’s emerging technologies group actually supplies tracking cameras to stores. RetailNext, based in San Jose, Calif., uses video footage to study how shoppers navigate. The company also uses data yanked from customer smartphones to deduce even more specific patterns. This is accomplished when the customer's device is hunting for a Wi-Fi network.

Thus, a store that offers Wi-Fi can pinpoint where the shopper is physically under its roof -- within a 10 foot radius -- even if the shopper hasn't joined the network. Stores also know when the customer has returned because the phone gives off its own unique identification code. Thus, a retailer not only knows the shopping patterns of repeat customers, but the duration between visits.

RetailNext also reportedly uses data to map actual customer paths: There's a 70 percent chance the customer will veer right, and there's a 14 percent chance the customer will linger at the display. Creepy.

The full two-page report can be read here. Needless to say, it may be a good idea for everyone to switch off Wi-Fi from now on outside the home unless they're specifically trying to access a store's wireless network.